Manlift

ABSTRACT

A manlift comprising a driven drum, a tension drum spaced vertically downwards from the driven drum and an endless belt trained about the spaced apart driven and tension drums. The endless belt has an upward travel and a downward travel on a respective opposed side thereof between the driven and tension drums. Guide means are provided adjacent each side edge of the endless belt and extends at least along the upward and downward travel. At least one tread support member is rigidly secured to the endless belt transversely thereto. The tread support member is displaceably engaged adjacent each side edge of the endless belt in a respective one of the guide means for maintaining the tread support member vertically along a predetermined path. Holding means are further provided to permit a person standing on the tread support member to secure himself while being transported by the endless belt.

United States Patent Fried] Oct. 7, 1975 MANLIFT Primary ExaminerEvon C. Blunk Assistant Examiner-James L. Rowland Vl l, 5 I F [76] Inventor si g: gg g 349 van ranko Attorney, Agent, or FirmD1ller, Brown, Ram1k &

Wight [22] Filed: Apr. 22, 1974 21 Appl. 110.; 462,728

[57] ABSTRACT A manlift comprising a driven drum, a tension drum [52] US. Cl. 187/l'6; 182/443; l87/222; spaced vertically downwards from the driven drum I 12 187/41 187/98 198/15 198/ 3 and an endless belt trained about the spaced apart [51] nt. C 866B 9/0 driven and tension drums The endless belt has an [58] held of Search 187/16 ward travel and a downward travel on a respective op- 187/98 198/154-1158 182/42 posed side thereof between the driven and tension 44 drums. Guide means are provided adjacent each side edge of the endless belt and extends at least along the [56] References cued upward and downward travel. At least one tread sup- UNITED STATES PATENTS port member is rigidly secured to the endless belt 308,721 12/1884 Whitehouse et a1. 182/43 transversely thereto. The tread support member is dis- 375,293 12/1887 Humphrey 187/16 placeably engaged adjacent each side edge of the end- 412,956 10/1889 H mp y--- 187/16 less belt in a respective one of the guide means for H1900 valfghn 182/43 maintaining the tread support member vertically along l a predetermined path. Holding means are further pro- 1 9,1949 zizfi igi 187,9 vided to permit a person standing on the tread support 2:862:577 12/1958 Deverenui: X member to secure himself while being transported by 2,908,498 10/1959 Becraft 187/16 x the endless belt- 3,592,294 7/1971 Allen 187/95 x 16 Claims, 6 Drawing Figures &: i

US. Patent Oct. 7,1975

FIG. 2

Sheet 1 of4 FIG. I

US. Patent 0a. 7,1975 Sheet 2 of4 3,910,383

FIG. 3

U.S. Patent Oct. 7,1975 Sheet 3 of4 Sheet 4 of4 3,910,383

U.S. Patent Oct. 7,1975

FIG 5 MANLIFI BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to elevators and more particularly to a manlift wherein a person can be transported between floors of a building by means of an endless belt trained about a driven and a tension drum located respectively on a top floor and a bottom floor of a building.

2. Description of the Prior Art Generally, a manlift is usually in continuous operation and does not require the services of an operator or attendant. A person can mount or dismount the endless belt while it is moving or if desired, the belt can be stopped and/or started by using a rope control which is located within easy reach of the person. Thus, a manlift provides a relatively economical means of transporting a person between floors of a building whilst utilizing a minimum amount of space.

Known manlift devices have various disadvantages which the present invention is believed to have overcome. For example, one known type manlift utilizes a drive which comprises a motor with a brake mounted on a speed reducer and connected to the drive shaft by a slow speed flexible coupling. Other units have a safety brake mounted on the end of the drum shaft. The disadvantage which this provides is that the drive drum can assume a free-wheeling state wherein the endless belt cannot be positively stopped. A further disadvan:

tage is that the steps or tread supports of prior art devices consist of an assembly of two treads mounted on side brackets with guide rollers andjoin in a scissor-like arrangement with the whole unit being bolted to the belt by a connecting bar between each pair of side brackets. This type of arrangement can become disengaged as the tread support member is not always in engagement with guide means.

Still further disadvantages with prior art devices is that the hand holds or hand grip members are connected to the belt only, which allows the person to pull the belt away from the structure simply by leaning away from the belt while holding the hand hold. This sometimes results in injury of the person while passing through a floor opening as the person is not in close proximity to the endless belt. A still further disadvantage is that the lower drum of existing structures is equipped with either manual tcnsioning device, which consists of two adjacent screws on the drum shaft or an automatic tensioner which requires the shaft to be mounted into two vertically guided counterweights. This sometimes results in that the drum is not in a horizontal plane and this causes the tread support member to become unaligned and disengaged. Still further, existing manlifts have safety treadles in the area under the descending step but do not protect the area under the drum proper. This means that an object could fall or be placed under the lower drum and obstruct the passage of these steps or tread support.

SUMMARY OF THE INVENTION It is a feature of the present invention to provide a manlift which substantially overcomes all the above mentioned disadvantages. Accordingly, there is provided an improved drive system for the manlift whereby the endless belt can be positively stopped.

Furthermore, it is a feature to provide an improved tensioning assembly. Still further, the present invention provides a tread support and a grip member which is rigidly secured to the endless belt and which is in guided engagement throughout the travel of the belt. Still further, the present invention provides safety means to positively stop the endless belt when the belt has stretched beyond a predetermined limit or when a person is conveyed to an unwanted area.

Accordingly, from a broad aspect the present invention provides a manlift comprising a driven drum, a tension drum spaced vertically downwards from the driven drum and an endless belt trained about the spaced apart driven and tension drum. The endless belt has an upward travel and a downward travel on a respective opposed side thereof between the driven and tension drum. Guide means are provided adjacent each side member to secure himself while being transported by the endless belt.

BRIEF DESCRIPTION OF THE DRAWINGS A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a side elevation illustrating an installation of the manlift of the present invention;

FIG. 2 is a top view of the manlift;

FIG. 3 is a fragmented plan view of a portion of the manlift illustrating the drive assembly, the tensioning assembly, the tread support member and grip member;

FIG. 4 is a sectional fragmented side view substantially of the lower portion as shown in FIG. 3;

FIG. 5 is a fragmented side view of the lower support frame illustrating the safety treadle, and

FIG. 6 is a plan view of the safety treadle.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and more particularly to FIGS. 1 and 2 there is shown generally at 10 the manlift of the present invention, As shown the manlift extends along a vertical axis and between a plurality of floors 11 in a building. Passage means 12 are provided in each floor whereby the manlift 10 extends through these floors. As shown, the manlift consists primarily of an endless belt 13 trained about a driven drum l4 and a tension drum 15. The driven drum is secured to the top floor ll of the building whilst the tension drum is secured close to the lower floor 11" of the building. A plurality of tread support members 16 are secured in spaced apart relationship to the endless belt 13. Additionally, holding means, hereinshown in the form of a hand grip member 17 are also secured to the endless belt 13 at a predetermined location above each tread support member 16. Normally a platform 18 is positioned adjacent the manlift whereby a person can embark onto the manlift by climbing the platform 18 and stepping onto a tread member 16 as it comes adjacent the platform. The person is then carried upwardly through the passage means 12 in the floors. Normally a safety bonnet 19 is provided below the entrance means 12 of each floor on the upward travel of the endless belt. Hereinshown, the upward travel is designated by arrow 20 whilst the downward travel is on the opposite side of the endless belt and designated by arrow 21..

Referring now to FIG. 3 of the drawings there is shown the drive assembly as comprising an upper support frame 31 having side brackets 32 supporting a drive shaft 33 in a horizontal plane therebetween and located in self-aligning bearings 34 secured in the side brackets 32. The driven drum 14 is generally cylindrical and is provided with side walls 29:. The driven drum is also secured to the drive shaft 33 between the side brackets 32. A safety brake 37 is mounted on the support frame 31 and about the drive shaft 33 and is connected directly to the side wall 29 of the driven drum by the flange shown at 38. This applies to the electromagnetic type disc brake, as herein shown. the brake 37 is a standard type electromagnetic disc brake as is known in the art and for that reason will not be described in detail herein as its construction does not form part of this invention. However, this type brake will stop the drum positively to prevent free-wheeling of the endless belt 13. The driven shaft 33 extends beyond the side bracket 32 adjacent the side wall 29 of the driven drum and connects to a drive means 25 consisting essentially of a brake type motor 35 and a speed reducer 36. A drum or shoe type brake may also be utilized instead of the disc type brake 37. In such a case, a brake drum is provided by means of a cylindrical flange (not shown) built integral with the driven drum.

The outer surface of such flange may also provide h guide means for the wheels 71 described later. Furthermore. the motor 35 or brake 37 may be located on either side of the driven drum 14, or both on the same side, depending on the application of the manlift.

Referring now to FIGS. 3 and 4 there is shown generally at 40, the tensioning assembly. The tensioning assembly 40 for tensioning the endless belt 13 comprises a tension drum 15 supported on a free-hanging horizontal shaft 41 guided by a parallelogram frame 42.

Each end 43 of the horizontal shaft 41 is provided with a circular flange 52 displaceably held in a vertical guide or channel 44 provided in the lower support frame 45. The tension drum 15 is weighted whereby to provide the required tension in the endless belt which is trained about this drum.

It is important to maintain the horizontal shaft 41 in a horizontal plane whereby the outer periphery of the tension drum 15 will be in flat engagement with the endless belt 13. This is achieved by the parallelogram frame 42 which comprises two vertical side arms 47 each pivotally secured at a top end 47' to a respective end 43 of the horizontal shaft 41. Each vertical side arm 47 has a lower end 49 pivotally secured to one end of a respective lower pivotal arm 50. The opposite end of the lower pivotal arm 50 is secured to a fixed fulcrum 51 with the fulcrum 51 of each lower pivotal arm lying on a common horizontal axis whereby the freehanging horizontal shaft 41 is maintained horizontally by the parallelogram frame. Thus, the parallelogram frame is herein defined as comprising the parallel combination of shaft 41 and the common horizontal axis passing through the fulcrums 51 and also the combination of the two parallel arms each made up of a side arm 47 and a pivotal arm 50.

The shaft 41 is secured in bearings (not shown) and located in a respective bearing housing 48 formed inte grally about the center of each side wall 81 of the tension drum 15. The area between the guide flanges 53 eonsitutes the vertical channel 44. Thus, it can be seen that the shaft is also held against side displacement in the lower supporting frame 45. As shown in phantom lines in FIG. 4 the horizontal shaft 41 and consequently the tension drum 15 can move vertically in the channel 44 and between the guide flanges 53. This travel is caused by the elasticity of the endless belt 13. In use the belt will be stretched and become longer to cause the tension drum to move lower within the channel. However, this travel is limited to a predetermined range which is indicated as being the area 54 delineated between an upper limit axis 55 and alower limit axis 56, all within the channel 44. The upper limit 55 and lower limit 56 are sensed by switch means which are actuablc by the position of the parallelogram frame 42. whereby the driven drum and the endless belt will be stopped automatically when the horizontal shaft 41. is beyond the predetermined range 54 either at its upper or lower limit.

A switch 57 is secured to the lower support frame 45 and is actuable by displacement of the parallelogram frame when the end of the shaft exceeds the upper or lower limits of the predetermined range 54. This is achieved by the provision of an areuate bar 58 having a projecting end finger 58 and 58 at a respective end of the bar 58. The bar is secured adjacent its lower end to the end of a lower pivotal arm 50and adjacent its end which is in pivotal connection with the vertical arm 47.

The armature of the switch 57 is provided with a roller 57 which is spring biased against the surface of the arcuate bar 58. The switch 57 will not be activated when the roller 57' travels between the fingers 58 and 58" or when the parallelogram frame is displaced between its position shown in FIG. 4 in full line to its position shown in phantomlines at 59 and corresponding to the area 54. As soon the parallelogram frame exceeds the limits of the area 54, the roller 57 will ride up one of the fingers 58' or 58" causing the armature of the switch to be displaced to activate the switch,

which in turn will cause the driven drum and endless belt to stop. The arcuate member 58 has an are lying in the same plane as the arcuate path of a fixed point on the arm 50 displaceable aboutthe fulcrum 51;

With reference again to FIGS. 3 and 4 there is shown the construction of the tread support member 16 as comprising two spaced apart parallel side frames interconnected in parallel relationship by means of a transverse securing bar 67 in which is secured at its ends by suitable seeurement means 68 to a respective side frame 65. The securing bar 67 is connected to the endless belt 13 by means of a plurality of rivets or securing screws 69. A support member 70 is secured be tween the parallel side frames 65 and extends transversely and forwardly of the endless belt 13. Follwer means hereinshown as wheels 71 are each secured at a respective end of the parallel side frame 65 for guided engagement within guide means 100. The guide means consists of an elongated U-shape channel member 101 positioned adjacent each side edge 13 of the endless belt 13 and having a bottom wall 102 and integrally formed opposed sidewalls 103 whereby to define an open end 104 (see also FlG. 2.).

Each wheel 71 is provided with a flange 71 extending about and above the edge ofthe wheel closest to the side frame 65. The flange 71 has a diameter which is larger than the distance transversely of the channel open end. That is to say, the distance transversely of the sidewalls 104. A safety pin 72 is secured to a respective end of the two parallel side frames 65 adjacent a respective wheel 71 and extends into the open end of the channel member 101. This provides for safety of the assembly should one of the wheels 71 break away. It can be seen that the safety pin 72 would still ride within the channel and maintain the tread support member 70 in the guided path defined by the channel member 101. lnstead of the pins 72 there may be provided extension finger members formed integrally with side frames 65.

The grip member 17 consitutes a holding means for a person being transported by the endless conveyor. The person stands on the tread support member 70 and holds the grip member 17 with his hand. Hereinshown, the grip member is constituted by a rigid bracket having a securing wall 75 for attachment to the endless belt 13 such as at 76. A hand grip member 77 is integrally formed on the securing wall 75 and consists essentially of a forwardly extending cup. The securing wall 75 extends beyond each side edge 13' of the endless belt 13 and is also provided with follower means or wheels 71. Hereinshown. a single wheel 71 is secured to each end and extends in guided engagement within a respective U-shape channel member 101. It is conceivable that the holding means may be provided adjacent the end less belt. For example, there could be provided a rigid elongated member on each travel side of the belt providing grip means for a person riding up or down the manlift.

It can be seen from FIGS. 3 and 4 that the channel member is secured between the upper support frame 31 and the lower support frame 45. Also, reinforcing structural members (not shown) may be provided throughout the length of the manlift to secure the channel member 101 in spaced apart relationship and to solidify the frame work. As shown in FIG. 3, the tension drum is further provided with an annular horizontal flange 80 on each side wall 81 thereof. The flange 80 is spaced inwardly of the outer circular periphery of the drum whereby to guide the wheels 71 as they rotate about substantially the lower half portion of the drum 15. As shown in FIG. 4, it can be seen that the channel member 101 extends vertically upward from the lower limit axis 56 of the predetermined range 54 and in alignment with the annular flange 80 on one side of the tension drum 15. The channel member 101 then follows the side edge 13 of the endless belt 13 and forms an arcuate upper path adjacent the upper portion of the periphery of the driven drum 14 then extends vertically downward to terminate in alignment with the annular flange 80 but on the opposite side of the tension drum 15. Thus, the tread support member and the hand grip member follow a guided path defined by the channels 101 and the flange 80 on the tension drum whereby these members are held in a horizontal plane throughout the travel and cannot be pulled away from their engagement with the endless belt causing the endless belt to be maintained in a predetermined plane.

Referring now to FIGS. 5 and 6. there is shown the construction of the safety treadle 90. The safety treadle comprises a flat frame 94 pivotally connected at one end 92 to the lower support frame 45. The other end or free end 93 of the frame 94 is urged upwardly from the plane of its pivotal connection and its end 92 by means of a spring 95 located under the frame 94. Further, the free end of the frame extends outwardly from the lower support frame on the downward travel side 21 of the endless belt 13. The switch 91 is actuable when the frame 94 is depressed downwardly whereby to stop the driven drum and the endless belt. Thus, any foreign object which is dropped or lodged below the tension drum will cause the endless belt to stop. Also, if the person being carried in the downward direction touches this extension portion, the belt will stop thus preventing the person to have any body portion trapped between the tread member undergoing its travel under the tension drum.

Referring to FIG. 4, there is shown a modification of the tread support member 16. Hereinshown, in solid lines the support member 70 is secured between the parallel side frames substantially adjacent an end thereof whereby to form a substantially L-shape tread support when viewed from the side. With this type of arrangement the support member will start inclining away from the endless belt 13 at its lowest height from the bottom floor before the tread support member begins its travel about the tension drum. As shown in phantom lines the support member 70 may be secured substantially centrally of the two side frames 65 to form a T-shape tread support member when viewed from the side.

I claim:

1. A manlift comprising a driven drum, a tension drum spaced vertically downwards of said driven drum, said tension drum having an annular guide flange in each side thereof and spaced inwardly of its outer circular periphery, means maintaining said tension drum in a horizontal plane, an endless belt trained about said spaced apart driven and tension drum, said endless belt having an upward travel and a downward travel on a respective opposed side thereof between said driven and tension drum, guide means adjacent each side edge of said endless belt and extending at least along said upward and downward travel, at least one tread support member rigidly secured to said endless belt transversely thereto, said tread support member having two spaced apart parallel side frames, a transverse securing bar connected at each its ends to a respective side frame, said securing bar being connected to said endless belt, a support member secured between said parallel side frames and extending transversely and forwardly from said belt, and follower means secured at each end of each said parallel side frame for guided engagement with said guide means and for further guided engage ment with a respective one of said annular guide flange in each side of said tension drum whereby to guide said tread support member about said tension drum and maintain said tension belt substantially centrally about a portion of said tension drum, said follower means being displaceably engaged adjacent each side edge of said endless belt in a respective one of said guide means for maintaining said support member vertically along a predetermined path, and holding means permitting a person standing on said tread support member to secure himself while being transported by said endless belt.

2. A manlift as claimed in claim 1 wherein said follower means is a wheel rotatably secured adjacent each end of each said side frames and being held in said guide means.

3. A manlift as claimed in claim 2 wherein said guide means is an elongated U-shape channel member positioned adjacent each side edge of said endless belt and having a bottom wall, integral opposed side walls and an open end.

4. A manlift as claimed in claim 3 wherein said wheel is provided with a flange extending about and above an edge of said wheel, said flange having a diameter which is larger than the distance transversely of said channel open end.

5. A manlift as claimed in claim 2 wherein an extension member is secured to a respective end of said two parallel side frames adjacent each wheel and extends into said guide means.

6. A manlift as claimed in claim 1 wherein said holding means is a grip member rigidly secured to said end less belt and spaced a predetermined distance from said tread support member.

7. A manlift as claimed in claim 6 wherein said grip member is a rigid bracket having a securing wall for attachment to said endless belt, a hand grip member on said securing wall and extending forwardly of said endless belt, said securing wall extending beyond each side edge of said endless belt and having follower means secured at each end thereof for guided engagement with said guide means.

8. A manlift as claimed in claim 7 wherein said follower means is a wheel rotatably secured to each said ends of said securing wall, said wheel having a flange extending about and above an edge of said wheel, said guide means being an elongated U-shape channel member having a bottom wall, integral opposed side walls and an open end, said flange having a diameter which is larger than the distance transversely of said channel open end.

9. A manlift as claimed in claim 1 wherein said driven drum is secured to a drive shaft supported on bearings in a frame, said drive shaft extending beyond each side wall of said driven drum, drive means coupled to said shaft on one side of said driven drum, a safety brake about said shaft on one side of said drum, said safety brake being secured directly to the said driven drum to prevent freewheeling of said driven drum when said brake is operated.

10. A manlift as claimed in claim I wherein said means maintaining said tension drums in a horizontal plane comprises a parallelogram frame for guiding a free-hanging horizontal shaft on which said tension drum is supported, each end of said horizontal shaft being displaceably held in a vertical channel provided in a support frame, said drum being weighted to provide the required tension in said endless belt held about said driven and tension drums.

11. A manlift claimed in claim 10 wherein said parallelogram frame comprises two vertical, side arms each pivotally secured at a top end to said horizontal shaft on a respective side of said tension drum, each vertical side arm having a lower end pivotally secured to one end of a respective lower pivotal arm, said lower pivotal arm having an opposite end pivotally secured to a fixed fulcrum, said fulcrum ofeach said lower pivotal arm lying on a common horizontal axis whereby said free hanging horizontal shaft is maintained horizontally by said parallelogram frame.

12. A manlift claimed in claim 10 wherein said vertical channel is provided by two spaced apart vertical guide flanges each end of said shaft being displaceably held between said two guide flanges for travel within a predetermined range, said predetermined range having upper and lower limits which are sensed by switch means actuable by the position of said parallelogram frame whereby to stop said driven drum and said endless belt.

13. A manlift as claimed in claim 12 wherein there is an arcuate member secured to said, parallelogram frame, said switch means being an electrical switch having an armature associated with said arcuate member, said armature causing activation of said switch when displaced by a predetermined position of said arcuate member when said end of said shaft exceeds said upper or lower limit of said predetermined range.

14. A manlift claimed in claim 12 wherein said guide means being an elongated U-shape channel member positioned adjacent each side edge of said endless belt and having a bottom wall, integral opposed side walls and an open end, each said open end of said U- shape channels extending vertically upwardly from said lower limit of said predetermined range and in alignment' with said annular flange on one side of said tension drum and following its respective side edge of said endless belt thereby forming an arcuate upper travel adjacent an upper portion of theperiphery of said driven drum and then extending vertically downwardly to terminate in alignment with said annular flange on an opposite side of said tension drum, whereby said annular flange provides tracking means for guiding said follower means about the lower circumferential periphcry of the tension drum and providesreengagement of said follower means into said guide means.

15. A manlift as claimed in claim I wherein there is further provided a safety treadle and located a predc-= termined distance below said tension drum, said safety treadle comprising a member pivotally connected at one end to said support frame and urged upwardly at the end opposite said pivotally connectedend, said opposed end extending outwardly of said support frame on said downward travel side of said endless belt, switch means associated with said member and actuable when said member is depressed downwardly whereby to stop said driven drum and said endless belt.

16. A manlift as claimed in claim 1 wherein said endless belt extends between a plurality of floors in a build-.

ing, each floor having a passage for said endless belt and'for a person being transported on said tread support member on either said upward or downward travel of said belt, said driven drum being secured above a top floor of said building, said tension drum being secured on a bottom floorof said building, said endless belt having a plurality of spaced apart tread support members secured thereto. 

1. A manlift comprising a driven drum, a tension drum spaced vertically downwards of said driven drum, said tension drum having an annular guide flange in each side thereof and spaced inwardly of its outer circular periphery, means maintaining said tension drum in a horizontal plane, an endless belt trained about said spaced apart driven and tension drum, said endless belt having an upward travel and a downward travel on a respective opposed side thereof between said driven and tension drum, guide means adjacent each side edge of said endless belt and extending at least along said upward and downward travel, at least one tread support member rigidly secured to said endless belt transversely thereto, said tread support member having two spaced apart parallel side frames, a transverse securing bar connected at each its ends to a respective side frame, said securing bar being connected to said endless belt, a support member secured between said parallel side frames and extending transversely and forwardly from said belt, and follower means secured at each end of each said parallel side frame for guided engagement with said guide means and for further guided engagement with a respective one of said annular guide flange in each side of said tension drum whereby to guide said tread support member about said tension drum and maintain said tension belt substantially centrally about a portion of said tension drum, said follower means being displaceably engaged adjacent each side edge of said endless belt in a respective one of said guide means for maintaining said support member vertically along a predetermined path, and holding means permitting a person standing on said tread support member to secure himself while being transported by said endless belt.
 2. A manlift as claimed in claim 1 wherein said follower means is a wheel rotatably secured adjacent each end of each said side frames and being held in said guide means.
 3. A manlift as claimed in claim 2 wherein said guide means is an elongated U-shape channel member positioned adjacent each side edge of said endless belt and having a bottom wall, integral opposed side walls and an open end.
 4. A manlift as claimed in claim 3 wherein said wheel is provided with a flange extending about and above an edge of said wheel, said flange having a diameter which is larger than the distance transversely of said channel open end.
 5. A manlift as claimed in claim 2 wherein an extension member is secured to a respective end of said two parallel side frames adjacent each wheel and extends into said guide means.
 6. A manlift as claimed in claim 1 wherein said holding means is a grip member rigidly secured to said endless belt and spaced a predetermined distance from said tread support member.
 7. A manlift as claimed in claim 6 wherein said grip member is a rigid bracket having a securing wall for attachment to said endless belt, a hand grip member on said securing wall and extending forwardly of said endless belt, said securing wall extending beyond each side edge of said endless belt and having follower means secured at each end thereof for guided engagement with said guide means.
 8. A manlift as claimed in claim 7 wherein said follower means is a wheel rotatably secured to each said ends of said securing wall, said wheel having a flange extending about and above an edge of said wheel, said guide means being an elongated U-shape channel member having a bottom wall, integral opposed side walls and an open end, said flange having a diameter which is larger than the distance transversely oF said channel open end.
 9. A manlift as claimed in claim 1 wherein said driven drum is secured to a drive shaft supported on bearings in a frame, said drive shaft extending beyond each side wall of said driven drum, drive means coupled to said shaft on one side of said driven drum, a safety brake about said shaft on one side of said drum, said safety brake being secured directly to the said driven drum to prevent freewheeling of said driven drum when said brake is operated.
 10. A manlift as claimed in claim 1 wherein said means maintaining said tension drums in a horizontal plane comprises a parallelogram frame for guiding a free-hanging horizontal shaft on which said tension drum is supported, each end of said horizontal shaft being displaceably held in a vertical channel provided in a support frame, said drum being weighted to provide the required tension in said endless belt held about said driven and tension drums.
 11. A manlift as claimed in claim 10 wherein said parallelogram frame comprises two vertical side arms each pivotally secured at a top end to said horizontal shaft on a respective side of said tension drum, each vertical side arm having a lower end pivotally secured to one end of a respective lower pivotal arm, said lower pivotal arm having an opposite end pivotally secured to a fixed fulcrum, said fulcrum of each said lower pivotal arm lying on a common horizontal axis whereby said free hanging horizontal shaft is maintained horizontally by said parallelogram frame.
 12. A manlift as claimed in claim 10 wherein said vertical channel is provided by two spaced apart vertical guide flanges each end of said shaft being displaceably held between said two guide flanges for travel within a predetermined range, said predetermined range having upper and lower limits which are sensed by switch means actuable by the position of said parallelogram frame whereby to stop said driven drum and said endless belt.
 13. A manlift as claimed in claim 12 wherein there is an arcuate member secured to said parallelogram frame, said switch means being an electrical switch having an armature associated with said arcuate member, said armature causing activation of said switch when displaced by a predetermined position of said arcuate member when said end of said shaft exceeds said upper or lower limit of said predetermined range.
 14. A manlift as claimed in claim 12 wherein said guide means being an elongated U-shape channel member positioned adjacent each side edge of said endless belt and having a bottom wall, integral opposed side walls and an open end, each said open end of said U-shape channels extending vertically upwardly from said lower limit of said predetermined range and in alignment with said annular flange on one side of said tension drum and following its respective side edge of said endless belt thereby forming an arcuate upper travel adjacent an upper portion of the periphery of said driven drum and then extending vertically downwardly to terminate in alignment with said annular flange on an opposite side of said tension drum, whereby said annular flange provides tracking means for guiding said follower means about the lower circumferential periphery of the tension drum and provides reengagement of said follower means into said guide means.
 15. A manlift as claimed in claim 1 wherein there is further provided a safety treadle and located a predetermined distance below said tension drum, said safety treadle comprising a member pivotally connected at one end to said support frame and urged upwardly at the end opposite said pivotally connected end, said opposed end extending outwardly of said support frame on said downward travel side of said endless belt, switch means associated with said member and actuable when said member is depressed downwardly whereby to stop said driven drum and said endless belt.
 16. A manlift as claimed in claim 1 wherein said endless belt extends between a plurality of floors in a building, each floor having a passage For said endless belt and for a person being transported on said tread support member on either said upward or downward travel of said belt, said driven drum being secured above a top floor of said building, said tension drum being secured on a bottom floor of said building, said endless belt having a plurality of spaced apart tread support members secured thereto. 